Short test terminal



June 17, 1941. A. w. GRAHAM SHORT TEST TERMIIYAL Filed June 30, 1939 MWm. H 2 Z m w w m h y m H. 4 w w M vfippw IIIII/ I Patented June 17,1941 SHORT TEST TERMINAL Audrey W. Graham, Ashville, Ohio, assignor, bydirect and mcsne assignments, to Russell B.

Arnold, Chicago, 111.

Application June 30, 1989, Serial No. 282,189

4 Claims. (Cl. 200-158) This invention relates to connecting meansbetween terminals designed to permit quick testing of circuits betweenthose terminals, and finds one particular use in railroad signalingbrackets where circuits have to be tested quite frequently. It is aprimary object of the invention to provide an exceedingly simplestructure that may be employed in close spacing of terminals. Theinvention consists essentially of means interconnecting two terminalsfor normal circuit conditions and providing a terminal nut that may beunscrewed slightly to interrupt the circuit and permit an additionalconnection between the terminals independently of the normal connection.In this regard reference is made to the United States Patent No.2,145,041 issued to S. C. Childers, January 24, 1939. The presentinvention is intended to be used in the same manner as suggested by thatpatent but lends itself to use where the terminals are more closelyspaced than it is possible with the use of the terminal connection inthat patent.

These and other objects and advantages of the invention will becomeapparent to those versed in the art in the following description of theinvention as illustrated in the accompanying drawing, in which Fig. l isa top plan view of a structure embodying the invention;

Fig. 2, a central longitudinal section through the structure; and

Fig. 3, a detail in centralvertical longitudinal section of a modifiedform.

Like characters of reference indicate like parts in the two views of thedrawing.

A pair of terminals l and H are herein shown as having heads embedded ina block of insulating material 12, each terminal having an appreciablelength extending from the block I2. In many of the modern installations,these terminals will be spaced in signal brackets as close as one inchfrom center to center. Wires l3 and M are connected to the respectiveterminals l0 and I l in the usual manner between the securing nuts l5,l6 and l1, l8.

To interconnect the two terminals l0 and II, I form a band or flat bar19 of suitable conducting material, such as copper or bronze, to haveone end perforated preferably in the nature of an elongated slot 20 topermit the strip l9 to be placed down over one of the terminals,terminal H in the present case, and have a securing nut 2 l drawn downsnugly thereagainst by its screwthreaded connection with the terminal IIto compress the strip 19 between that nut 2| and the underlying nut H.

The other end of the band i9 is offset upwardly to have an insulatingblock 22 under that offset portion, the thickness of the block beingsuch that its under surface is then substantially in or slightly abovethe plane of the underside of the major portion of the strip 19. Theoffset portion of the strip 19, designated by the numeral 23, isprovided with a hole therethrough through which an insulating collar 24is inserted and carried down through the under block 22. A hollow rivetor ferrule 25 is entered from the underside of the collar and carriedtherethrough to have a flange 26 extend outwardly and come into contactwith a portion of the block 22 surrounding the collar 23. This ferrule25 extends upwardly through the collar 2iand is preferably rolled overby its top end onto the top side of the collar 24 in order to retain theferrule in position. The collar 24 fits snugly within the block 22 toprevent its withdrawal therefrom. It is to be noted that the top edge ofthe collar 24 terminates at or slightly above the plane of the top sideof the offset portion 23 of the strip It. This provides a sufficientspacing between the upper end of the ferrule 25 and the offset portion23 as will prevent the establishment of any normal circuit thereacross.

As indicated in Fig. 2, the flange 25 extending from the ferrule 25bears against the top side of the securing nut l5. A nut 21screw-threadedly engages the terminal Hi and is provided with a lowerend having a diameter exceeding that of the collar 24, and this lowerend is counterbored so that the nut 21 may be carried down on theterminal H] to have a peripheral portion come into contact with theoffset portion 23. By seating the nut 21 snugly against the strip, acircuit is then established between the terminals 10 and II through theterminal Ill, nut 27, offset portion 23, remainder of the strip l9, nut2|, and terminal ll. Jam nuts 23 and 29 are employed on the respectiveterminals Ill and II to secure the seating of the nuts 2'! and 2!. Toprevent turning in the insulating block 22 in respect to the strip I9,the offset portion 23 is preferably provided with a detent 3i]projecting downwardly from the underside thereof and entering into theblock 22.

When the circuit is to be tested, the nuts 28 and 21 are loosened andcarried upwardly along the terminal ID a suflicient distance as willpermit the nut 21 to have its lower peripheral end portion removed fromcontact with the offset end 23 of the strip l 9. Connection may then bemade by entering a wire between the nuts 2! and 28 and tightening themagain relatively one toward the other. In this manner, connection isbroken directly between the terminals I and Hv simply by raising the nut21. The circuit is re-established by lowering the nut 27 and securing itagainst the end 23.

As illustrated in Fig. 3, the block 22 may be secured to the offset end23 of the strip H? by forming the upper end of the ferrule 25 withexternal threads about an upper projecting end in place of rolling thisend outwardly over the collar 2 3. An insulating washer 3| is placedover the end 23 to surround the ferrule 25 and extend outwardly a slightdistance onto the end 23 therearound. A jam nut 32 is thenscrewthreadedly engaged about the upper end of the ferrule 25 and drawndown to compress the washer Jl against the upper end of the collar 24and also against the end 23. The nut 21 is made sufficiently large inrespect to its counterbore to clear the nut 32 so that there is noelectrical circuit established between that member and the nut 27. Thefirst form above described, however, is the one that may be made morecheaply and will generally suffice under ordinary conditions.

While I have herein shown and described my invention in the form as nowbest known to me, it is obvious that structural changes may be employedwithout departing from the spirit of the invention and I, therefore, donot desire to be limited to that precise form beyond the limitations asmay be imposed by the following claims.

I claim:

1. For a test terminal for use with a pair of spaced apart terminalposts, a conductor bar having an opening through one end and the otherend offset also with an opening therethrough, an insulating memberfilling in under the offset end, a spacing collar extending into theopening through the hole in said offset end and through the insulatingmember, a ferrule extending through the collar having collar impingingmeans at the ends of the ferrule, said bar having the openings thereinspaced one from the other to receive said posts therethrough, a nut onthe post which passes through the hole in the opposite end of theconductor bar from the offset end of the bar, and a nut on the postpassing through the hole in said offset end, said last nut having itsunderside counterbored to clear said collar and to form an annularperipheral portion of the nut normally compressively engaging saidoffset portion of the bar.

2. For a test terminal for use with a pair of spaced apart terminalposts, a conductor bar having an opening through one end and the otherend offset also with an opening therethrough, an insulating memberfilling in under the offset end and having a spacing collar extendinginto the opening through the hole in said offset end, said bar havingthe openings therein spaced one from the other to receive said poststherethrough, a nut on the post which passes through the hole in theopposite end of the conductor bar from the offset end of the bar, and anut on the post passing through the hole in said offset end, said lastnut having its underside counterbored to clear said collar and to forman annular peripheral portion of the nut normally compressively engagingsaid offset portion of the bar, a metallic ferrule extending throughsaid collar, a laterally extending flange on the ferrule extending overonto said insulating member, and means at the other end of the ferruleengaging over the end of said collar.

3. For a test terminal for use with a pair of spaced apart terminalposts, a conductor bar having an opening through one end and the otherend offset also with an opening therethrough, an insulating memberfilling in under the offset end and having a spacing collar extendinginto the opening through the hole in said offset end, said bar havingthe openings therein spaced one from the other to receive said poststherethrough, a nut on the post which passes through the hole in theopposite end of the conductor bar from the offset end of the bar, and anut on the post passing through the hole in said offset end, said lastnut having its underside counterbored to clear said collar and to forman annular peripheral portion of the nut normally compressively engagingsaid offset portion of the bar, a metallic ferrule extending throughsaid collar, a laterally extending flange on the ferrule extending overonto said insulating member, and means at the other end of the ferruleengaging over the end of said collar, said means comprising a turnedover flange having its peripheral margin spaced from said bar.

4. For a test terminal for use with a pair of spaced apart terminalposts, a conductor bar having an opening through one end and the otherend offset also with an opening therethrough, an insulating memberfilling in under the offset end and having a spacing collar extendinginto the opening through the hole in said offset end, said bar havingthe openings therein spaced one from the other to receive said poststherethrough, a nut on the post which passes through the hole in theopposite end of the conductor bar from the offset end of the bar, and anut on the post passing through the hole in said offset end, said lastnut having its underside counterbored to clear said collar and to forman annular peripheral portion of the nut normally compressively engagingsaid offset portion of the bar, a metallic ferrule extending throughsaid collar, a laterally extending flange on the ferrule extending overonto said insulating member, and means at the other end of the ferruleengaging over the end of said collar, said means comprising a nutscrew-threadedly engaging the end of said ferrule, and said last postnut having its counterbore sufficiently large to clear said ferrule nut.

AUDREY W. GRAHAM.

